Nights stay kind in Llanelli each January, milder than in 92% of UK towns
On a normal July day the thermometer tops out near 20.8°C (69°F). Rain is plentiful here, more than falls on 91% of UK towns. From frosty January to warm July, readings climb 18°C. The outdoor season runs from June to September, with highs of 18–21°C.
Met Office 1991–2020 averages for the town itself.
A year in Llanelli at a glance
Each month’s typical high and low, in °C.
What a year in Llanelli feels like
Typical highs and lows by season and by month, from the Met Office’s 1991–2020 averages.
About 1,243 mm of rain a year
October is the wettest month and April the driest. About 40 days a year bring 10 mm (0.4 in) or more. 15th wettest of 23 Dyfed towns of 2,500+.
Rain by month
Millimetres
Sunshine by month
Hours of bright sunshine at Aberporth
30 air frosts and 9 days of 25°C a year
On about 30 nights a year the air drops below freezing; days that stay below freezing are rare. About 9 days a year reach 25°C (77°F).
Day counts are 1991–2020 averages from the Met Office’s 2 km grid. The Met Office calls a day of 25°C or more a summer day and a night below 0°C an air frost; ground frosts, on grass, come more often.
The Met Office station at Aberporth
Aberporth is 36 miles north-west of Llanelli, 133 m (436 ft) above sea level. It is the nearest of the 37 long-running stations the Met Office publishes in full; at that distance read it for sunshine and the station’s own record, not as the town’s figures.
| Month | High | Low | Rain | Air frosts | Sun (hours) |
|---|---|---|---|---|---|
| January | 7.8°C | 3.4°C | 90 mm | 4.5 | 60 |
| February | 7.9°C | 3.3°C | 67 mm | 3.8 | 79 |
| March | 9.4°C | 4.2°C | 58 mm | 1.8 | 127 |
| April | 11.6°C | 5.7°C | 54 mm | 0.4 | 172 |
| May | 14.3°C | 8.2°C | 55 mm | 0.0 | 210 |
| June | 16.6°C | 10.7°C | 64 mm | 0.0 | 203 |
| July | 18.3°C | 12.5°C | 67 mm | 0.0 | 187 |
| August | 18.3°C | 12.7°C | 75 mm | 0.0 | 169 |
| September | 16.7°C | 11.2°C | 71 mm | 0.0 | 141 |
| October | 13.6°C | 8.9°C | 107 mm | 0.0 | 99 |
| November | 10.5°C | 6.2°C | 117 mm | 0.6 | 59 |
| December | 8.5°C | 4.1°C | 107 mm | 3.5 | 49 |
| Year | 12.8°C | 7.6°C | 931 mm | 15 | 1,554 |
Met Office historic station data, Aberporth, 1991–2020 months averaged (a month needs 20 of the 30 years; estimated values counted, missing months left out). Sunshine: Kipp & Zonen recorder.
How Llanelli compares
Against the 2,537 towns and cities of 2,500 or more across the UK, each with its own Met Office averages, and its place among Dyfed towns that size.
Nearby towns’ climate
The nearest towns of 1,000+ within 12 miles: a hill, a valley or the sea can make a real difference over a few miles.
| Town | July high | January low | Rain a year |
|---|---|---|---|
| Llanelli | 20.8°C | 2.9°C | 1,243 mm |
| Bryn 2.0 mi | 21.0°C about the same | 2.9°C about the same | 1,257 mm |
| Pwll 2.3 mi | 20.4°C about the same | 2.5°C about the same | 1,224 mm |
| Llangennech 2.8 mi | 21.0°C about the same | 3.0°C about the same | 1,328 mm |
| Pen-clawdd 3.5 mi | 21.0°C about the same | 2.9°C about the same | 1,332 mm |
| Loughor 3.8 mi | 21.0°C about the same | 3.0°C about the same | 1,267 mm |
| Burry Port 4.4 mi | 20.4°C about the same | 2.5°C about the same | 1,190 mm |
Llanelli weather by month
Average daily high and low, mean temperature and rain, 1991–2020, for the town itself (the Met Office’s HadUK-Grid).
| Month | High | Low | Mean | Rain |
|---|---|---|---|---|
| January | 8.3°C 47°F | 2.9°C 37°F | 5.6°C | 132 mm 5.2 in |
| February | 8.5°C 47°F | 2.7°C 37°F | 5.6°C | 94 mm 3.7 in |
| March | 10.6°C 51°F | 4.0°C 39°F | 7.3°C | 85 mm 3.3 in |
| April | 13.6°C 57°F | 5.5°C 42°F | 9.5°C | 73 mm 2.9 in |
| May | 16.6°C 62°F | 8.2°C 47°F | 12.4°C | 74 mm 2.9 in |
| June | 19.2°C 67°F | 11.1°C 52°F | 15.1°C | 79 mm 3.1 in |
| July | 20.8°C 69°F | 12.9°C 55°F | 16.8°C | 90 mm 3.6 in |
| August | 20.5°C 69°F | 12.8°C 55°F | 16.6°C | 100 mm 4.0 in |
| September | 18.3°C 65°F | 10.7°C 51°F | 14.5°C | 96 mm 3.8 in |
| October | 14.7°C 59°F | 8.0°C 46°F | 11.4°C | 141 mm 5.6 in |
| November | 11.1°C 52°F | 5.2°C 41°F | 8.2°C | 140 mm 5.5 in |
| December | 8.8°C 48°F | 3.1°C 38°F | 5.9°C | 139 mm 5.5 in |
| Year | 14.3°C | 7.2°C | 10.7°C | 1,243 mm |
Where Llanelli’s numbers come from
Averages over 30 years, not a forecast.
- Mean temperature, rain and day counts: HadUK-Grid 1991–2020 averages for the 3 Met Office 2 km grid squares whose centre lies inside Llanelli’s built-up area.
- Highs and lows: the Met Office publishes average daily maxima and minima on its 12 km grid; each is moved by the difference between the town’s 2 km mean temperature and the 12 km square’s, which carries the town’s own height and setting over.
- Weather station and sunshine: Met Office historic station data for Aberporth, 36 miles away, months of 1991–2020 averaged.
- Comparisons: every town and city of 2,500 or more across the UK, all four nations, read the same way.
Met Office HadUK-Grid · Met Office Climate Data Portal · Historic station data. Open Government Licence v3.0.
Questions about Llanelli’s climate
How warm does Llanelli get in summer?
July is the warmest month, with average highs of 20.8°C (69°F). About 9 days a year reach 25°C (77°F), fewer than 59% of UK towns.
How cold does Llanelli get in winter?
February nights average 2.7°C (37°F). The air drops below freezing on about 30 nights a year, and about under 1 days a year stay below freezing all day.
How much rain does Llanelli get?
About 1,243 mm (49 in) a year, more than 91% of UK towns. October is the wettest month (141 mm) and April the driest (73 mm).
How sunny is it?
The nearest Met Office station with a sunshine record, Aberporth (36 miles away), averages 1,554 hours of bright sunshine a year. Sunshine isn’t on the town grid, so this is the station’s figure.
Where do these figures come from?
The Met Office’s HadUK-Grid 1991–2020 averages, which turn thousands of weather stations into a map of the UK in 2 km squares; the page reads the squares inside Llanelli. They are 30-year averages, not a forecast.
Contains Met Office data © Crown copyright 2026, Open Government Licence v3.0. HadUK-Grid 1991–2020 averages via the Met Office Climate Data Portal; station averages from Met Office historic station data. Today’s forecast for Llanelli →
Contains public sector information licensed under the Open Government Licence v3.0. Contains HM Land Registry data © Crown copyright and database right 2026. Contains OS data © Crown copyright and database right 2026 (ONS boundaries). Northern Ireland: Source: NISRA; contains Land & Property Services data and Ordnance Survey of Northern Ireland information, © Crown copyright, licensed under the Open Government Licence v3.0. Scotland: contains National Records of Scotland data, Registers of Scotland data and SEPA data, © Crown copyright / © SEPA 2025, licensed under the Open Government Licence v3.0.